1. Field of the Invention
The invention relates to an arrangement for protecting an electrical facility from overvoltages with an overcurrent protection facility arranged in a first series circuit and a shunt circuit arranged between the overcurrent protection facility and the electrical facility to be protected, where the shunt circuit leads to a second series circuit, where a diode for discharging transient overvoltages is arranged in the shunt circuit, and where the diode is designed to be conductive, if a voltage threshold is exceeded, as a result of which the current resulting from the overvoltage can be passed through the shunt circuit to the facility to be protected into the second series circuit.
2. Description of the Related Art
It is common knowledge that with voltage supplies to electrical devices, it is conventional to arrange a suppressor diode downstream of a device fuse to limit overvoltages. The disadvantage with this known arrangement, however, is that brief voltage pulses may cause the device fuse to prematurely trigger. The device fuse is as a rule designed to only trigger in the event of static overvoltages or overcurrents. It is not desirable, however, for the device fuse to already trigger on account of premature voltage pulses.
One known solution is to circumvent the problem of designing the device fuse such that an increase in its responding behavior is achieved, which may result in problems in the case of a real fault, because the device to be secured is possibly still briefly supplied with an overcurrent.